Sensors: LiMo3Se3 Nanowires as Programmable Chemical Sensors

传感器：LiMo3Se3 纳米线作为可编程化学传感器

• 批准号: 0427418
• 负责人: Frank Osterloh
• 金额: --
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2009-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0427418&HistoricalAwards=false
• 关键词: Sensors; LiMo3Se3; Nanowires; Programmable; Chemical

AbstractCTS-0427418F. Osterloh, U of Cal DavisSensors: LiMo3Se3 Nanowires as Programmable Chemical SensorsA versatile electrochemical sensor for the rapid and selective detection of chemical warfare agents, glucose, explosives and for other molecules in the gas and liquid phases is proposed. The sensor is based on arrays of nanometer thick films of metallic LiMo3Se3 nanowires that are dispersed between two or several gold electrodes. Upon exposure to solvent vapors the nanowires undergo large (240%) and reversible changes of their conductivity. The electronic response depends on the nature of the solvent and on the concentration, and it occurs within seconds of the exposure. The selectivity of the nanowires can be controlled by covalently linking receptors to the selenide surface of the nanowires. Upon attachment of propionic acid (a proton receptor) the nanowire film becomes a detection element for protons in aqueous solution. A similar pH sensor also forms by linking 10 nm large gold nanoparticles to the wires, and by subsequently attaching 3-mercaptopropionic acid to the gold nanoparticles.In order to use the LiMo3Se3 nanowires for sensors that will be faster, smaller, more sensitive and versatile and less expensive than sensors based on conventional materials, it is planned to systematically study the structure, physical and electrical properties of LiMo3Se3 nanowires under variable conditions. The conductivity response of the nanowires to molecules or variable charge, polarity and coordinating power will be measured using patterned indium tin oxide microelectrode arrays that allow simultaneous interrogation of up to twenty different nanowire films. The number of molecules/ions that interact with the nanowires under given conditions will be determined with quartz crystal microbalance measurements. Systematic covalent modifications of the nanowires with small molecules and with oligopeptides will be conducted to introduce receptors for the selective detection of chemical warfare agents, for glucose and for explosives. Scanning tunneling measurements on modified nanowires will probe changes of the electronic structures that occur as a result of these modifications and that are due to analyte interactions.Accompanying electronic structure and molecular dynamic calculations will simulate the observed phenomena, and develop models to rationalize the effects.In being able to detect glucose, explosives, and chemical warfare agents, thenanowire based sensors that will be fabricated in this project will directly contribute to health care and national security. In establishing a molecular level understanding of the physical and chemical aspects of molecule-nanowire interactions this project will make also a general impact on the design and understanding of nanowire sensors.Graduate and undergraduate students will be involved in all aspects of the project. They will prepare the materials and characterize them with instruments that they operate independently, and they will present their results at conferences. Collaborations with physical and theoretical chemists and with a physicist will strengthen the communication across disciplines. Results from the project will be incorporated into exhibits at a local science museum and into chemistry demo shows on campus and at local high schools.This K-12 outreach initiative will involve the UC Davis chemistry club, an organization of 20 undergraduate students with different majors which is overseen by the PI. During an open door day undergraduate students will be given the opportunity to visit the lab and to make contact with the respective PIs. An graduate course on "Inorganic Colloids" will be offered as an introduction to the chemistry and physics of colloidal particles and their uses for engineering applications, and in particularly to sensor technology.

摘要CTS-0427418 F。Osterloh，加州大学戴维斯分校传感器：LiMo 3Se 3纳米线作为可编程化学传感器提出了一种多功能电化学传感器，用于快速和选择性检测化学战剂，葡萄糖，爆炸物和气相和液相中的其他分子。该传感器基于分散在两个或几个金电极之间的金属LiMo 3Se 3纳米线的纳米厚膜阵列。当暴露于溶剂蒸气时，纳米线的电导率发生大的（240%）和可逆的变化。电子响应取决于溶剂的性质和浓度，并且在暴露后几秒钟内发生。纳米线的选择性可以通过将受体共价连接到纳米线的硒化物表面来控制。在附着丙酸（质子受体）后，纳米线膜成为水溶液中质子的检测元件。类似的pH传感器也通过将10 nm大的金纳米颗粒连接到导线上，然后将3-巯基丙酸连接到金纳米颗粒上而形成。为了将LiMo 3Se 3纳米线用于比基于常规材料的传感器更快、更小、更灵敏和通用且更便宜的传感器，计划系统地研究其结构，LiMo 3Se 3纳米线在不同条件下的物理和电学性质。纳米线对分子或可变电荷、极性和配位能力的电导率响应将使用图案化的氧化铟锡微电极阵列来测量，该阵列允许同时询问多达20种不同的纳米线膜。在给定条件下与纳米线相互作用的分子/离子的数量将用石英晶体微量天平测量来确定。系统的共价修饰的纳米线与小分子和寡肽将进行引入受体的选择性检测化学战剂，葡萄糖和爆炸物。对修饰纳米线的扫描隧道测量将探测由于这些修饰以及分析物相互作用而发生的电子结构的变化。伴随的电子结构和分子动力学计算将模拟观察到的现象，并开发模型来合理化效果。在能够检测葡萄糖，爆炸物和化学战剂方面，该项目中制造的基于纳米线的传感器将直接有助于医疗保健和国家安全。在建立分子水平上对分子-纳米线相互作用的物理和化学方面的理解时，该项目也将对纳米线传感器的设计和理解产生普遍的影响。研究生和本科生将参与该项目的各个方面。他们将准备材料，用他们独立操作的仪器来表征它们，他们将在会议上介绍他们的结果。与物理和理论化学家以及物理学家的合作将加强跨学科的沟通。该项目的成果将被纳入当地科学博物馆的展览中，并在校园和当地高中进行化学演示。这一K-12推广计划将涉及加州大学戴维斯分校化学俱乐部，该俱乐部由20名不同专业的本科生组成，由PI监督。在开放日期间，本科生将有机会参观实验室，并与各自的PI接触。将提供一门关于“无机胶体”的研究生课程，介绍胶体颗粒的化学和物理及其在工程应用中的用途，特别是传感器技术。